Manouevring mode of vehicles having an automated clutch

ABSTRACT

A motor vehicle ( 2 ) has a transmission ( 6 ) with an automated clutch ( 8 ) with a control device ( 20 ), a gas pedal, a brake pedal and an actuating element ( 28, 30, 32 ) which is released for activating an inching procedure. In the method for determining a defined inching procedure, time is measured by the actuating element ( 28, 30, 32 ) after the inching procedure has been activated and, after a reference value has been exceeded, the inching procedure starts at a predeterminable speed as long as neither the brake pedal nor the gas pedal has been activated.

[0001] According to the preamble of claim 1 the invention relates to a manoeuvring mode for vehicles with automated clutch.

[0002] In vehicle transmissions constructed without a clutch pedal, for many manoeuvring operations it is desirable to leave the right foot upon the brake pedal which is generally used for giving gas and thus for delivering a reference value signal for the torque in order to be able very quickly brake the vehicle in an emergency should a dangerous torque appear.

[0003] EP 0 731 294 A2 has disclosed a manoeuvring mode for vehicles with automated transmissions. There it is proposed, depending on an inching mode selected by the driver, to adapt the gas pedal inclination so as to allow, for a corresponding injection amount, a larger actuating angle than in a different driving mode. The vehicle in this mode can be moved at a lower speed under an equal adjustment angle of the gas pedal. The method has the disadvantage that the driver has to leave his right foot upon the gas pedal for determining the manoeuvring speed. In the event of a dangerous torque, he has to change pedals to be able to brake.

[0004] The problem on which this invention is based is to outline a method that allows a quick action upon decelerating devices of the vehicle.

[0005] The problem is solved by a method having the features stated in claim 1. Developments are object of sub-claims.

[0006] In a method for determining a defined inching procedure of a motor vehicle, the vehicle has an automated clutch with a control device, a gas pedal and a brake pedal, and the vehicle has an actuating element for activating the inching procedure. The time after activation of the inching procedure by the actuating element is measured and compared with a reference value. After exceeding the continues while neither the brake pedal nor the gas pedal is activated. In one embodiment, the activation of the inching procedure is confined to the activated driving steps for the automated forward gear range or the reverse gear range. An elimination of activation of the inching procedure must be avoided especially in the “parking” and “neutral” control positions in order not to allow an unintended release of the vehicle movements. One design of the invention allows activation of the inching procedure only in the activated driving steps for the reverse gear range. In one embodiment, the actuating element is controlled by hand, that is, the driver manually engages the actuating element in the area of the control elements for the vehicle which are located in an area accessible to his hands. But in another embodiment, the actuating element is actuated by the foot which does not actuate the brake pedal. One other embodiment provides that a control element, for a function of the vehicle which constitutes an unnecessary function during the inching procedure, can be used as the actuating element so that hereby an additional actuating element can be spared. As control elements for this, for example, a hand lever for actuating an additional brake device such as a retarder or an engine brake switch actuatable by hand or foot are considered. A combined actuation of several switches can also be used for activating the inching procedure.

[0007] In an advantageous embodiment, different fixed manoeuvring speeds are preset in the control device which can be called via the actuating element. In one development of the invention, the manoeuvring speed is selected by determining the time of uninterrupted actuation of the actuating element and coordinating a specific manoeuvring speed with a specific time elapsed and, in another embodiment, the manoeuvring speed is selected by determining the number of actuating operations of the actuating element and coordinating a specific manoeuvring speed with a specific number of actuations. In one advantageous development, the idling speed regulator is engaged, for example, via a vehicle master for correcting the idling rotational speed according to engaged auxiliary consumers which otherwise would lower the idling rotational speed and no longer ensure the desired manoeuvring speed.

[0008] In the layout of the possible manoeuvring speeds and also of the period during which said speeds can occur, on the basis of the defined clutch differential speed related to the manoeuvring speed, the load capacity of the clutch has to be kept in mind. To this end can serve a limitation of the maximum torque of the clutch or clutch protection functions must be provided in case of overload of the clutch during protracted operation. When using rotational speed sensors of the vehicle whose minimum detectable rotational speed lies below the rotational speeds achieved in the manoeuvring operation. It is also possible to control the manoeuvring operation by the signals about the existing engine torque which can be read from the injection amount and the knowledge, via engaged auxiliary consumers, the same as the differential rotational speed occurring on the clutch.

[0009] The invention explained in detail with reference to a drawing which shows:

[0010]FIG. 1 diagrammatically shows a vehicle with automated transmission;

[0011]FIG. 2 is a selector switch;

[0012]FIG. 3 is a rotary switch on the selector switch;

[0013]FIG. 4 is one other switch;

[0014]FIG. 5 one switch in the foot area; and

[0015]FIG. 6 one control element of other vehicle functions.

[0016]FIG. 1 shows a vehicle with a primer mover 4, a transmission 6 and a clutch 8 situated therebetween. The transmission 6 has a main part 10, a splitter group transmission 12 and a range change group transmission 14. The transmission 6 is connected by connecting lines 18 with an electronic control device 20. A selector switch 16 is provided for delivering manual engagements of the driver and is connected with the control device 20. The transmission 6 is automatically shifted by an adjusting device 22 according to signals that the adjusting device 22 receives from the control device 20. The clutch adjuster 24 likewise receives signals from the control device 20 and actuates the clutch 8.

[0017]FIG. 2 shows a selector switch 16 which has a selector lever 26 and a rotary switch 28. The selector switch 16 is connected with the control device 20.

[0018] In FIG. 3, the rotary switch 28 is shown in more detail. Next to the neutral position “N” is provided a position “R” for the reverse gear range, a position “A” for the automatically engaged forward gear range and a position “M” for the manually engaged forward gear range. The position “X1” represents a position of the rotary switch 28 in which the inching procedure is activated in the reverse gear range and which is logically provided in direction to the position “R” from neutral. The position “X2” represents a position of the rotary switch 28 in which the inching procedure is activated in the forward gear range and which logically is provided in direction to the positions “A” or “M” from neutral.

[0019]FIG. 4 shows a switch 30 which can be situated upon the dashboard of a driver compartment or also on the selector switch 16 and likewise can serve as alternative design for activating the inching procedure.

[0020] In FIG. 5 is finally shown an alternative for a switch 32 actuated by a foot. The switch 32 is rotatable around an axis AA on the body in the foot space of the driver compartment and comprises a base plate 34 in the form of a foot pedal upon which is situated a plate 36 pivotable around an axis BB. The base plate 34 has a slot 38 in which a pin 40 engages in the plate 36 whereby the deviation path of the plate 36 is limited. The switch 32 is connected with the control device 20 via a connection 42. A stop 44 is provided laterally on the plate 36 against which a shoe edge of the vehicle driver can be pressed. Unlike in FIG. 5A, in FIG. 5B the plate 36 is sidewise displaceable upon the base plate 34, the pin 40, in turn, being passed into the slot 38 thus limiting the path thereof.

[0021] In FIG. 6, a steering wheel 48 is provided on a dashboard 46 of the driver compartment, on which is placed a steering drop arm 50 for control of a retarder. The steering drop arm 50 is adjustable in different positions along a semicircle 52, shown here as lines, through which the different braking steps are controlled. At low speeds the retarder is inactive. Therefore, the control element steering arm drop 50 can be used in this driving situation for activating the inching procedure.

[0022] Reference numerals 2 vehicle 28 rotary switch 4 prime mover 30 switch 6 transmission 32 switch 8 clutch 34 base plate 10 main part of transmission 36 plate 12 split group transmission 38 slot 14 range change group transmission 40 pin 16 selector switch 42 connection 18 connecting line 44 stop 20 control device 46 dashboard 22 adjusting device 48 steering wheel 24 clutch adjuster 50 steering drop arm 26 selector lever 52 semicircle 

1. Method for determining a defined inching procedure of a motor vehicle (2) having an automated clutch (8), a control device (20), a gas pedal, a brake pedal and an actuating element (28, 30, 32), which is released for activating the inching procedure, characterized in that the time after activation of the inching procedure by said actuating element (28,30,32) is measured, and after a reference value is exceeded, the inching procedure starts at a predeterminable speed and is maintained until either brake pedal or gas pedal is activated.
 2. Method according to claim 1, characterized in that the automated clutch (8) is connected with an automatic or automated transmission (6) and that the activation of the inching procedure is limited to the activated driving steps for the automated forward gear range or the reverse gear range.
 3. Method according to claim 1 or 2, characterized in that the activation of the inching procedure is limited to the activated driving steps for the reverse gear range.
 4. Method according to any one of claims 1 to 3, characterized in that said actuating element (28, 30) is manually controlled.
 5. Method according to any one of claims 1 to 3, characterized in that said actuating element (32) is actuated by the driver with the foot that does not actuate the brake pedal.
 6. Method according to any one of claims 1 to 5, characterized in that said actuating element (28, 30, 32) is the control element (50) of another function not needed in the inching procedure.
 7. Method according to any one of claim 1 to 6, characterized in that in said control device (20) different fixed speeds are preset which can be called via said actuating element (28, 30, 32).
 8. Method according to any one of claims 1 to 7, characterized in that the speed is selected by the time of the uninterrupted actuation of said actuating element (28, 30, 32).
 9. Method according to any one of claims 1 to 7, characterized in that the manoeuvring speed is selected by the number of actuation operations of said actuating element (28, 30, 32).
 10. Method according to any one of claim 1 to 5, characterized in that the signal of an idling speed regulator of the prime mover (4) in said control device (20) is corrected according to engaged auxiliary consumers. 